The finish on a fiberglass bathtub can scratch and wear off over the years. Usually, having the paint finish rub off isn't going to actually affect the waterproof quality of the fiberglass. The actual fiberglass is waterproof itself, but you do need to worry if the fiberglass starts to rub down and get thinner. If the fiberglass becomes too exposed, it can become weaker, and there is a greater risk of cracking. This is why it is so important to refinish fiberglass bathtubs when such blemishes start to appear. This article shows the best tools and techniques for doing so.
You will only need to use fiberglass cloth if there is an actual hole in your bathtub. Usually, you can buy a kit that includes both fiberglass resin and the cloth. However, if you are just trying to refinish the fiberglass, you only need the resin. The resin comes with a liquid hardener that you mix in just before you apply. It will dry very quickly once the two substances are mixed together, so you want to be fully prepared.
Prepping the Spot
Before you can actually apply the resin, you need to do some important prep work. You need to lightly sand the damaged area and a small perimeter around it. This very subtly roughs up the fiberglass and gives it a slightly rough texture, which is very important for the resin. The resin will stick better to a rougher surface.
Fiberglass sandpaper is similar to traditional wood sandpaper, only it is much smoother. It probably won't remove much of the paint. When you are done sanding, you can apply the resin. A thin coat of resin, when applied with a putty knife, will reseal the fiberglass and protect it from wearing down. However, it is not going to dry completely flat and smooth.
Finishing the Patch Job
You will need to get out an even finer grit fiberglass sandpaper to smooth out and shape the patch job. Once your patch is dry and sanded, the final step is to apply the touch up paint. Fiberglass paint can be very runny, and you need to apply it using a fine brush. Some paint will actually come with the brush.
Ultimately, it might be impossible to perfectly cover your patch, but it is better to have a patched blemish then one that is still exposed and vulnerable to water damage. If you need help patching your fiberglass tub or run into any other complications, contact companies like Eager Beaver Handyman Services.